How predator incursions affect critical patch size: the role of the functional response

Area of Science:

• Ecology
• Mathematical Biology
• Conservation Biology

Background:

• Habitat fragmentation creates edges, influencing species interactions.
• Cross-boundary subsidies, like predator subsidies, affect community dynamics.
• Understanding habitat structure and scale is crucial for ecological insights.

Purpose of the Study:

• To model how predator intrusions affect prey dynamics in habitat patches.
• To investigate critical patch size effects induced by predators.
• To determine the role of predator functional responses in these effects.

Main Methods:

• Utilized a partial differential equation model.
• Simulated a patch-resident prey species and a generalist predator in the matrix habitat.
• Analyzed predator functional responses (Lotka-Volterra, Type II, Type III).

Main Results:

• Predator intrusions can induce critical patch size effects for prey, even without inherent prey dynamics causing them.
• Critical patch size effects are dependent on the predator's functional response.
• Lotka-Volterra and Type II functional responses generated critical patch size effects, unlike Type III.

Conclusions:

• Predator-induced critical patch size effects can significantly alter metapopulation dynamics.
• These effects influence the fraction and spatial distribution of viable patches for prey persistence.
• Conservation strategies must consider predator-prey dynamics at habitat edges.